1. Technical Field
The present invention relates to an optical filter device, an optical module, and an electronic apparatus.
2. Related Art
In the past, there has been known a measurement device for measuring the light intensity of light having a predetermined wavelength out of incident light using a Fabry-Perot etalon element (an optical filter device) (see, e.g., JP-A-01-94312 (Document 1)).
In the device described in Document 1, the distance between a pair of reflecting films constituting the optical filter device is varied by controlling an applied voltage to an actuator, and the light having a wavelength corresponding to a gap dimension between the reflecting films is transmitted and then received by a light receiving element.
Incidentally, in such a measurement device as described in Document 1 described above, in the case in which it is required to measure spectroscopic characteristics with respect to a broad wavelength band, it is preferable to use a metal film made of Ag alloy or the like as the pair of reflecting films constituting the optical filter device. However, in the case of using such a metal film, the half bandwidth of the light transmitted through the optical filter device becomes large, and the resolution is decreased. Therefore, it results that the light in the broad wavelength band centered on the wavelength on which the light intensity measurement has been performed is emitted from the optical filter device, and there is a problem that it is not achievable to obtain an accurate measurement result.